1. Field of the Invention
The invention relates to a method of installing an IC tag, such IC tag is attached to an item and is capable of preventing the misuse of information recorded therein.
2. Description of the Related Art
The use of IC tags has received much attention as a next generation of recognition technology that replaces the use of barcodes and IC tags are expected to be used in various fields such as manufacturing and distribution. The technology is also expected as essential technology for an upcoming “ubiquitous society.” As the use of IC tags has become more prevalent, leakage of information recorded in IC tags or the misuse of IC tags such as replacing them may increase.
There is a known IC tag structure as a technique of protecting against unlawful use of IC tags, according to which an IC tag attached to an item cannot be reused once it is removed from the item (see Japanese Patent Publication No. 2003-346121). The IC tag structure includes an antenna and a communication circuit on the substrate, and a short-circuiting part is additionally provided through a delaminating layer that promotes delamination into layers. The surface of the substrate is covered with a protective sheet with a delaminating protective layer therebetween. When the protective sheet is removed, the short-circuiting part is destroyed by delamination caused by the delaminating layer and removed together with the protective sheet, which disables the communication circuit.
However, the IC tag function is disabled while the IC chip including a memory that stores information is intact, and therefore the information recorded in the memory can be stolen from the IC chip or the IC chip itself can be misused. The information recorded in the IC chip must be deleted using a reader/writer or the reading function must be stopped by flag operation. However, this is possible only when an appropriate reader/writer is available. On this account, another IC tag structure has been proposed that allows the IC chip to be mechanically destroyed (see Japanese Patent Publication No. 2000-293658).
In the disclosed IC tag structure, a thin grooved part is formed on the opposite side to the surface for a semiconductor base circuit forming the IC chip, and the IC chip is mechanically destroyed from the thin part when external force is applied to the semiconductor base. When an IC tag including the IC chip is attached to an item and force is applied in an attempt to remove the IC chip, the IC chip is mechanically destroyed, and therefore the information recorded in the IC chip is not read out.
As the IC tag has been reduced in size, however, the IC chip has come to be so small that one side of the chip is less than 1 mm. It would be extremely difficult to break down the small IC chip by force applied to the thin part and caused by the effect of peeling for example, and it is still uncertain whether the IC tag can surely be destroyed by the method.